TextController.cs

using UnityEngine;
using UnityEngine.UI;
using System;
using System.Linq;
using System.Collections.Generic;

/*
 * This code is not particularly good (and the "story" is even worse, it's only supposed to be amusing).
 * 
 * I'd even go so far as to say that the code is fairly bad. For one, it uses reflection when it probably
 * doesn't need to, not if I had done things differently at least but it *does* function. I only wanted
 * to learn a bit more about C# and make it slightly less cumbersome to add states, which has been achieved.
 * 
 * I was thinking about making the system more advanced but I want to move on to section four and beyond.
 * That said, maybe I'll come back to this later on and try to make it a little more advanced. If nothing
 * else, it is good practise for learning C# and improving at programming. In any case, feel free to do
 * whatever you want with it. Share how you'd do things differently or improve it yourself, if you'd like.
 * 
 * 
 * One idea was that the first sentence which tells you *where you are* could change depending on if it
 * was your first time in the area (A) or not (B). For example:
 * 
 * A: You walk out into the hall. It is rather dark and dingy.
 * B: You return back to the dimly lit hall.
 * 
 * 
 * Another idea was to make it so that options could have requirements. For example, you might need to find a
 * key before you can use a door. This could be handled by just having more states but if you do it that way
 * then complexity would quickly begin to spiral out of control.
 * 
 * 
 * A further idea was to make it so that you could have states that were sort of connected, which would be useful
 * if you had a lot of text. With the current system, if you had to split a state in two due to the length of the
 * text there would have to be a "continue reading" choice which is clunky.
 * 
 * 
 * One last idea was to make it so that instead of the choices being based soley on the state names, instead
 * you could specify the text. This would make the choices for the state "cell", for example, more natural:
 * 
 * 1: Use the computer
 * 2: Speak to the butler
 * 3: Approach the door
 */
public class TextController : MonoBehaviour {

	public Text text;

	private struct State {
		public string[] Choices;

		public State(string[] choices) {
			Choices = choices;
		}
	}

	private Dictionary<string, State> States = new Dictionary<string, State> {
		{"intro",     new State(new string[] {"cell"})},
		{"tryagain",  new State(new string[] {"intro"})},
		{"cell",      new State(new string[] {"computer", "butler", "bed", "door"})},
		{"computer",  new State(new string[] {"playgame", "cell"})},
		{"butler",    new State(new string[] {"cell"})},
		{"bed",       new State(new string[] {"patterns", "cell"})},
		{"playgame",  new State(new string[] {"panic"})},
		{"panic",     new State(new string[] {"tryagain"})},
		{"patterns",  new State(new string[] {"crackcode", "cell"})},
		{"crackcode", new State(new string[] {"rest", "dontrest", "cell"})},
		{"rest",      new State(new string[] {"tryagain"})},
		{"dontrest",  new State(new string[] {"cell"})},
		{"door",      new State(new string[] {"cell", "hall"})},
		{"hall",      new State(new string[] {"left", "cell"})},
		{"left",      new State(new string[] {"pickup", "hall"})},
		{"right",     new State(new string[] {"hall"})},
		{"pickup",    new State(new string[] {"read", "drop"})},
		{"read",      new State(new string[] {"gameover"})},
		{"drop",      new State(new string[] {"left"})},
		{"gameover",  new State(new string[] {"intro"})}
	};

	private bool stateSetup = false;

	private string currentState = "intro";

	public void StateIntro() {
		SetText(
			"You are in prison for a crime you didn't commit. By starting you in a prison, we can then " + 
			"compare our story to The Elder Scrolls, which makes our game sound better than it is but I " +
			"digress....\n\nYou are in a prison. This would be all well and good (it's a Norwegian prison) " +
			"however there is one problem. The world is about to end and only you know how to stop it...");
	}

	public void StateTryagain() {
		SetText(
			"You had one job. You have disappointed more than seven billion people and you should feel bad.");
	}
	
	public void StateCell() {
		SetText(
			"You are in your cell and you should probably try to to escape, so that you can save the world. " +
			"In your cell, there is a gaming PC, a king size bed and your personal butler.");
	}

	public void StateComputer() {
		SetText("This is no time to be playing video games!");
	}

	public void StatePlaygame() {
		SetText(
			"You become immersed in an open-world story-driven RPG and the next thing you know, almost an hour " +
			"has passed.");
	}

	public void StatePanic() {
		SetText(
			"Through the window, the skies are beginning to turn red like blood. All of a sudden, there is a bang " +
			"so loud that it ruptures your eardrums. You fall to the floor and begin to writhe around in intense " +
			"pain, holding your bleeding ears. There is an unfathomably bright flash and then... nothing.");
	}

	public void StateBed() {
		SetText(
			"The bed is a king size canopy bed, with red silk curtains. They are adorned with the most " +
			"wonderful golden patterns which are almost entrancing in their nature...");
	}

	public void StatePatterns() {
		SetText(
			"You study the patterns more closely. You can't shake the feeling that there is some kind of code " +
			"hidden within them.");
	}

	public void StateCrackcode() {
		SetText(
			"After some time, you determine that the idea of the curtains containing some kind of hidden code " +
			"is preposterous. You are feeling quite sleepy now, though. Perhaps you should rest your head?");
	}

	public void StateRest() {
		SetText(
			"Your lay on the bed. It is so indescribably comfortable and you quickly fall into a deep sleep, " +
			"during which the world ends.");
	}

	public void StateDontrest() {
		SetText("It's good that you seem to have your priorities in order.");
	}

	public void StateButler() {
		SetText("You don't actually have a butler. Sorry. We shouldn't lie to you like that.");
	}

	public void StateDoor() {
		SetText("You walk up to the door. It is open, for whatever reason.");
	}

	public void StateHall() {
		SetText(
			"You are in the hall. You can either turn left and walk down the hall, or you can go back " +
			"into your cell.");
	}

	public void StateLeft() {
		SetText("You head towards the left. After a few moments you come upon a letter, laid on the floor.");
	}

	public void StatePickup() {
		SetText("You bend down and pick up the letter. It is adressed to 'Player'");
	}

	public void StateDrop() {
		SetText("You throw the letter back on the floor. Although you should probably reconsider...");
	}

	public void StateRead() {
		SetText(
			"You read the letter...\n\n" +
			"Dear Player\n" +
			"We ran out of funding for the game at this point in the development cycle...\n" +
			"Our most sincere apologies. I guess this means that you win.\n\n" + 
			"Congratulations?"
		);
	}

	public void StateGameover() {
		SetText("You win!");
	}

	private void Update () {
		if (States.ContainsKey(currentState)) {
			if (stateSetup == false) {
				this.GetType().GetMethod("State" + FirstCharToUpper(currentState)).Invoke(this, null);
				this.AddChoices();
			}

			HandleInput();
		}
	}

	private void SetText(string input) {
		text.text = input + "\n\n";
	}

	private void AddChoices() {
		int index     = 0;
		State current = States[currentState];

		text.text += "What would you like to do?\n\n";

		foreach(string state in current.Choices) {
			index++;

			text.text += "\t" + index + ": " + state + "\n";
		}

		stateSetup = true;
	}

	private void HandleInput() {
		int index     = 0;
		State current = States[currentState];

		foreach(string state in current.Choices) {
			index++;

			if (Input.GetKeyDown((KeyCode) Enum.Parse(typeof(KeyCode), "Alpha"  + index)) 
			 || Input.GetKeyDown((KeyCode) Enum.Parse(typeof(KeyCode), "Keypad" + index))) {
				stateSetup   = false;
				currentState = state;
			}
		}
	}

	private static string FirstCharToUpper(string input)
	{
		if (String.IsNullOrEmpty(input)) {
			throw new ArgumentException("String input is null or empty.");
		}

		return input.First().ToString().ToUpper() + input.Substring(1);
	}
}